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IPDL/Getting started: Difference between revisions
Clarified the number of actors involved in a communication via a protocol
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== Protocols and actors == | == Protocols and actors == | ||
A protocol defines how actors communicate. There are exactly two actors involved in such a communication. So, while there may be many actor pairs, each pair communicating using the same protocol, the protocol definition applies only to a single pair of actors. This distinction becomes important when understanding message synchronization semantics and protocol state machines, discussed below. | |||
We'll introduce protocols and actors using the ''plugin modules'' described above. Recall that in this example, we have two processes: the browser process and the process in which the plugin module's code executes. There are two actors: the thread context in which the browser's plugin management code executes (in the browser process), and the thread on which the plugin's code executes (in the plugin process). | |||
We have chosen to codify the concept of ''parent'' and ''child'' actors in IPDL; we use "parent actor" to refer to the "more trusted" actor, and "child actor" to refer to the "less trusted" actor. In the case of plugins, the browser actor is the ''parent'', and the plugin actor is the ''child''. | We have chosen to codify the concept of ''parent'' and ''child'' actors in IPDL; we use "parent actor" to refer to the "more trusted" actor, and "child actor" to refer to the "less trusted" actor. In the case of plugins, the browser actor is the ''parent'', and the plugin actor is the ''child''. | ||